Over the last several years, the growth of cell phones and messaging devices has increased the need for keypads and button/key sets that are small and tightly spaced. In particular, small form-factor keyboards, including QWERTY layouts, have become smaller and more tightly spaced. With decreasing overall size, there has been greater focus on efforts to make individual keys more usable to a user. For example, keyboard design considers how readily the user can select or click (“clickability”) individual key structures of keyboard. The clickability may be affected by various factors, such as the individual key structure size and shape, as well as the spacing between key structures and the tactile response of individual key structures.
With the growth of small form-factor devices, such as cell phones and wireless messaging devices, design parameters may provide for smaller functional keypads, particularly with respect to keypads that provide character entry. For example, keyboard layouts have been designed using button structures and individual key orientations that reduce the overall surface area of the keypad. Such designs have often focused on QWERTY keyboard layouts, which normally require at least 26-50 individual keys.
In addition to a keyboard, mobile computing devices and other electronic devices typically incorporate numerous buttons to perform specific functions. These buttons may be dedicated to launching applications, short cuts, or special tasks such as answering or dropping phone calls. The configuration, orientation and positioning of such buttons is often a matter of concern, particularly when devices are smaller.
In addition to keypad design, the shape and design of the device housing is also of interest. Along with the display, button sets and/or the keypad are typically one of the limiting factors in the size of a device housing. Consideration is often needed for the geometry and size of the area of the housing that is to accommodate the various button sets (or vice-versa). Various factors and influences may affect the desired housing shape. For example, the shape of the device housing can be made contoured to better fit the user's hand, or to create a distinctive and identifiable shape. Concerns such as the overall thickness or length of the device often play an important role in the overall shape of the housing design.